Low
P3 on Worcester Bosch Greenstar R29 40 HE

Your boiler is currently performing an automated internal calibration or maintenance check and will resume normal operation once finished.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Maintenance in progress.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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